Visual celestial navigation instrument



April 15, 1952 F. H. HAGNER 2,593,141

- VISUAL CELESTIAL NAVIGATION INSTRUMENT Filed Nov. 19,'*1947 5 sheets-sheet 1 IN VEN TOR.

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April 15, 1952 F, H, HAGNER 2,593,141

VISUAL CELESTIAL NAVIGATION INSTRUMENT l Filed Nov. 19, 1947 5 Sheets-Sheet 2 IN VEN TOR. @gage/cf f Man/e April 15, 1952 F. H. HAGNER 2,593,141

VISUAL CELESTIAL. NAVIGATION INSTRUMENT Filed Nov. 19. 1947 s sheets-sheet s iNVENToR. @gp55/ce /X #4a/vae on line I2-I2 of Figure 9;

Patented Apr. 15, 1952 VISUAL cELEsTrAL NAvIGA'rIoN .INSTRUMENT Y p Frederick'H. Hagner, San Antonio, Tex. vApplication November 19, 1947, Serial No. 786,845

J s claims. (01.33451) This invention relates to a visual celestial navigation instrument, and has `for one of its objects the production 'of a simple and efficient .instrument for measuring the zenith distance.

altitude "andi relative bearing (azimuth) of a selected celestial body relative to the geographicalposition of the observer.

A further object 4of this invention is the production `of a'fvisual celestial navigation instrument for measuring the shortest distance between two points on"y a 'semisphere representing the horizontal system in nautical astronomy and celestial navigation.

.Another object of this invention is the production of a lsimple and eflicient means for recording of the path of a selected celestial body upon a semisphere as the body will be seen by an observer while traveling between two geographical points at a given rate of speed on a known date and time vof departure and arrival.

Other objects and advantages of the present `invention willjappear throughout the following specification ,and claims.

In `the drawings: l

.Figure 1 is a side elevationalview of the instrument with "a part of the semiphere bro-ken Figure 2 isf` fragmentary top plan view of the instrument;

VFigure 3 isl/aybottom planfview of the instrument;

Figure 4 is a. central vertical sectional view of the instrument,` certain parts beingbrokenaway,

andthe semiphere being shown partly vin elevation; I i

illustrating'the manner of locking the ball in a set position; y -I Figure 14 is a perspective view of the spring ring which is carried by the ball-leveling device;

Figure 5 is adiagrammatic view of the instrument illustrating one measuring problem;

Figure 6 is another diagrammatic view of the instrument illustrating another measuringprob- 4 i I Figure 7 is an view taken on line 'I--l of Figure 3;

\ Figure 8 is an' enlargedV fragmentary sectional view taken on line 8--8 of Figure 3;

1" Figure 9 vis a transverse sectional view of the gravity-controlled ball-level indicator; Figure 10 is a horizontal sectional view taken Online Ill-I0 of Figure 9;

[Figure 1l is a horizontal sectional view 'taken "on line II-II of Figure 9; f

Figure l2 is a horizontal sectional view talen Figure 13y is an enlarged transverse sectional view 'through a portion of the ball-level indicator enlarged fragmentary sectional Figure 15 is an enlarged fragmentary side elevational view lof the lever which oscillates the ball-locking and releasing disc of the ball-level indicator or register; ,y

' Figure 16 is a fragmentarysectional view of Vthe semisphere illustrating the coating which may be applied to the surface of the semisphere..

By referring to the drawings, it will be seen `that I0 designates 'a cup-shaped hanger frame,

having a supporting flange I Ifwhichis preferably annularand is secured in any desired manner to the top of an airplane A. or other support, such as a ship or the like. Screws I2 may be .used to anchor the hanger frame I0 in positionin a suspendedfmanner from a suitable support. The frame I0 is provided with a large central aperture I3i An eccentrically mounted light-control circular disc I4 is carried byv and fixed toa shaft l5, which shaft I5 is journaled toone sideof the center of cup-shaped hanger frame IIL-as shown in Figures 2 and 4. A suitable knob IIS-,is carried by the shaft I5 to facilitate therotation off the disc I4'within the socket Il formed in the upper face of the hangerV I0. Suitable `pin-receiving sockets I8 are formed in the frame lil-below the ,dise I4 Vfor receiving the spring-pressed lock-pin I9 which is carried by the disc I4 for locking the disc I4 ina selected rotated position and to-rselectively bring thecenter of the -feather edge aperture :2D ofthe disc I4, or the center.` luminous circle 2|. of the glass disc 2 2,o11` theluminous circle center 23 of the clear glassdisc 24, directly over the center of the aperture I3. The center of the feather edge aperture 20 4andthe `bottom edge of the dise I4 are aligned with gimbajl pins 25 whicharecarried by the'frame l0 and the gimbal pins 26 when-the gimbal ringsZl and 28 lare in alignment. The disc I4 may be rotated to bring'the center 20,12I or 23 -to a central posi- .tion over the center of the aperturev I 3. The 'opening '20 is used when using the sun as a sighting body, the luminous circle 2|.when usinga star as a sighting body, and the center 23 of the disc 24 when using themoon'as a sighting' body. The pin I9 will lock thediscl4 inthe desired-selooted-position Y. .u

As shown, and also as noted above, the-rings 2l and 28 are mounted in gimbals of any suitable construction, and oneoffthe pins 25 'carriesfa `threaded nut 29 to lock the ring 21 in a set or locked `positionwhen desired. Any type of1ocking means may be provided to lock the rings 21 and 28 in a set position, without departing from the spirit of the invention.

A transparent semisphere 3| is suspended from the bottom of the hanger and is provided with a lateral annular flange 32 to support and also to permit rotation of the semisphere 3| upon the hanger i0.V The gimbal ring 21 is pivoted to the hanger l0 by pins 25, and the gimbal ring 28 is pivoted to the ring 21 by the pins 26, the pins 26 being located at right-angles to the pins 25, as shown in Figure 3. The semisphere. 3| is fastened to the hanger frame |6 by means of a retaining ring plate 33. The semisphere 3| preferably is formed of plastic, clear glass, or other transparent material for use in sighting stars. and may be coated with a translucentcoating of a suitable type 34 in a manner as shownin Figure 16, when sighting the sun. The coating 34 on semisphere 3| may be in the nature of a photographic emulsion to photograph the path of the observed or sighting celestial body during an observersfiight from point of departure to vpoint of destination in somewhat the same man- 'transparent 'gravitycontrolled level indicator or .register 36 `is carried within the bottom of the vslemisphere 3|. at its central point, as shown in Figure `1, directly'below the aperture I3 of the hanger l0. The outer ring 28 is provided with a 360 azimuth scale 31 upon its outer face, as shown `in Figure l. A 90 altitude arc 38 is pivoted ata central point intermediate the ends of' thejhanger band by means of a bearing 39 and atransparent viewing glass 40 is passed centrally 'through the bearing 39 so as to view the ball level-registering device 36, .see Figure l. The

keep the ball 54 from rolling around the outer edge of the edge of the plate 53. The-se scallops 55 overlie the edge of the plate 53, and the retaining ring 56 is threaded into the casing 50 to retain the plate 53, as shown in detail in Figure 13. O-ver the ball 54 a second ground glass plate 51 is carried Vby a vertically movable collar 58. This plate 51 is preferablyv convex with a radius of curvature of eight and seven-eighths inches.

The plate 51 is clamped upon the collar 58 between the inwardly extending flange 59 and arc 38 provided with a longitudinal slot 4| andv carries a pair of parallel scales 42 and 43,

the scale 42 being marked 0 to 90 `from the pivot 39 totheiouter endand the scale 43 reading 90 to 0, or reverse relative to the scale 42. An index -Slide 44 is slidable longitudinally of'the arcV 38 Vand has a central reading glass or lens 45 havinga central sighting point. overlying the slot *4I- AScale-sighting slots 46 are formed inY the slide overlying the scales'42 and 43 to facilitate readingof these scales.

moved so` as to underlie'the viewing glass 40 when `viewing the ball level register. As shown in Figure 1, the upper end of the are 38 is provided with an inturned tongue 41 which travels The slide 44 may be in the channel 48'formed in therouter face off the ring 28- above the scale 31, to hold the parts together. A ships heading indicator 46 is suspended from'the hanger framejflange in a -manner tclear the arc 38, a's'the arc'38 is swung.

The 'hanger band 35 is formed of transparent.

plastic material.

' The gravitycontrolled ballelevel indicaton'or register 36 comprises a casing50 which is secured within the bottom aperture 5| of the semisphere 3|.. The casing 50 is provided with a central aperture 52 in which is securely tted a glass A 'one-eighth inch steel ball 54 rests vided with a plurality of scallops 55 around the outer edge of the glass plate 53, which serve to the threaded ring 66. The collarl 58 is provided with a laterally-extending annular flange 6|, and

a rotatable flat ring 62 is interposed between the ange 6| and the upper end of the casing 59,

as shown in detail in Figure 13. Depending lugs 63 are carried by the ange 6| and normally fit within the concave sockets 64 which are formed in the upper face of the ring 62. The lugs 63 are adapted to lift the flange 6| as the ring 62 is rotated in one direction, thereby causing the lugs 6| to ride up out ofthe sockets 64 and contact the upper surface of the ring 62. This movement will lift the glass 51 out of contact with the ball 54 and allow the ball 54 to freely roll upon the plate 53 under the pull of gravity. A spring pressure ring 65 presses downwardly upon the flange 6| and is anchored in position by meansy of the anchoring screws 66 which pass through thering V65, the elongated slots 61 of the ring 62, and are threadedl into the upper end of the casing 56. As the ring 62 is rotated in the opposite direction, the lugs 63 will fall into the4 sockets 64 and the pressure of the spring ring 65 will force the collar 58 downwardly and cause the glass 51 to instantaneously clamp the ball 54 against the plate 53 and lock the ball 54 in a set position to register the direction and degree ofy tilt of the instrument.

For the purpose of oscillating the ring 62 to lock and release the ball 54 as described above, I provide a pivoted lever 61 which is mounted upon the casing 50, as at 68, and is pivotally connected at its opposite end to the periphery of the ring 62. A remotecontrol flexible cable 69 is connected to the lever 61 and carries a pushbutton 16 at its opposite end. The flexible cable 69 is of the conventional type illustrated and passes along the inner face of the semisphere 3| and out through a suitable opening near the upper edge thereof. The free end of the cable 69 which carries thepush-button 19 hangs down to a convenient point where it is in easy `reach of an operator;

It is well-known that a knowledge of three systems is required'for understanding of nautical astronomy and celestial navigation, for instance:

1. The horizon system ,of altitude and azimuth is used to make observations and every observation made in nautical astronomy and celestial navigation depends upon some means of obtaining the zenith fpoint.` Y Y l 2. The geographic systemwhere latitude and longitude refer to points upon the earth, the equatork and through the longitude of Greenwich.

3. The equinoctial system where declination and Greenwich hour angle refer to points of the celestial sphere, the celestial equator, and the meridian of Greenwich.V Hence the declination and Greenwich hourfangle ,of a star (for example) in zenith, is the latitudeand longitude of the place of observation.

It is possible with this instrument to measure the angeln zenith distanceand azimuth relative bearing of a selected visible celestial body., i U

kWiththis instrument it is possible to keep a continuous sight. on a` selected visible d celestial body and to record the path oftravel of said body from the time` the body first appears on the horizon in the east until said body disappears below the Western horizon. By utilizing .the number 214er 218 altitude and azimuth table published by the Hydrographic Ofiice, a precomputed curve may be readily drawn on `the semisphere 3|. Y

It should be noted that the l semisphere 3| preferably may be of one half clear glass for observing stars, and the other half may be covered with a suitable frosting coating for observing the sun. A ray^ of light fromV the sun is cast through the/.feather edge aperture 20 and causes a small spot of` light to be cast upon the frosted portion of thesemisphere 3|. Accuratelytted gimbals are mounted so that the opening 20 and the gimbalsvare located at the geometrical center of the instrument.` The arc orV band 35 represents the observers meridian. Inrthe ycenterbf this arcfwhich, represents the zenith, is mounted a lens or glass 40 which is focused to the center of the ball 54. The 90 altitude arc 38 is connected to the outer ring 28 and is pivoted at the point on arc 35 Where the glass 40 is mounted. An indexislide 44 is Aslidable over the arc 38 and scales 42V and 43, and is also movable to register with the center mark 40of the glass 40 when viewing the center of the ball 54 to measure. thev the diagrammatic views'of Figures 5 and 6.

The operation is as follows:

1. The pilotsteers a compass course and a ray e of light from the sun passes through the aperture 20 and is`cast at S" on the semisphere 3| in Figure`5. The `pilot notes his time and stops the ball 5,4 in the level indicator 36by operating the push-button 10 to clamp the plate 51 against the ball 54 at the moment when the sun spot Sis steady or at restv upon the semisphere. 3|. The "pilotjplacesa pencil pointvrnark on the semisphere where the fsun spot appears. He then movesthe :glass 40 so that theV smallcircle 4|)EL is directly under the ball 54 which represents the zenith point from which measurement is made. He then locks the gimbals 25 and 25 and moves the arc 38 and index slide 44 in columniation with the mark on the semisphere 3 I.' The reading on the azimuth scale 31 gives the relative bearing (azimuth) at the point Where the arrow 38a registers with the azimuth scale i. e. (220). The position of the center of the index slide 44 relative to the azimuth ring 28v and scale 42 i. e. (65?) will give -the altitude' of the observed body and the position of the index slide 44 on the arc 33relative tothe scale 43 i. e. (25) will givethe vzenithdistance of thev observed body measuring from `the circle 40L of the glass40 to index 44. Byiusing the clear glass onthe semisphere 3|,

- and :selectivelyrotatingthe disc I4 to bring the central points 2| or 23 into proper central position measurements may be made in the same manner while observing other celestial bodies at night, see Figure 6 for example.

semisphere 3| for theobservation of the sun. and thedclear surface maybe used for 1other observations in which event a` pencil having a luminous. stylus for` placing a luminous mark on the globe may be used. Also a photographic emulsion `or material may be placed on the' semisphere.

The curvature of the glassplates 53 and 51 must be approximately of the same curvature or radius as the semisphere 3| to obtain accurate measurement. l The bowl-like member or semisphere 3| may beimade entirely of clear glass if desired for use in taking an observation from the stars or moon, andthe entire surface of the semisphere 3| may be coated with a frosting compound or a Vphotographic emulsion if itis so desired, in place of coating only one vhalf or a segment thereof. A line M to indicate the observers local meridian, is preferably etchedv upon the semisphere 3| to divide the heavensinto an easternand a western half when the line M `registers with 360 line on the azimuth scale 3,1. d

The conventionalV magnetic and" gyro compasses may be corrected for variation'and deviation at the observers location on the earth. YThis is accomplished by marking a series of points on the semisphere 3| which represent positions of a selected celestial body in the heavens 'at given intervals of time. Then by'heading the plane or ship in azimuth (ship being level at timeof observation) the ray of lightpassing through aperture 20 and cast upon the globe or semisphere 3| and registering with these marks at the calculated time, the 360 line on the azimuth scale 31 will represent true north. By comparing the ships heading 43 relative to the scale 31 with the heading on the Compasses at the time of observation, the error, if any, is visible.

Forinstance, the reading on scale 31 is ships heading 360 and at that time the magnetic compass may read ships heading 5, making a difference of 5 error in an easterly direction.

The spots or circles 2| and 23 may be placed upon the under faces of the members 22 and 24 so as to be inline with the bearings of the gimbal rings. v

Having described the invention, what is claimed is: l

l. A visual `celestiall navigation instrument comprising a support having a lightreceiving opening through which a ray of lightV from a celestial body is adapted to pass, `gimbal rings secured to said support, a hanger band suspended from one of said rings, an azimuth scale carried by one of the rings, an altitude and zenith` dis- 'light spot on said semisphere, and a scale car- "ried by said arc to measure the distance on said arc between the index and the azimuth scale to give the altitude of the observed bodyjand'to `measure the distancel between the index andthe pivot of the arc to give the zenith distance, the position of the arc relative to the azimuth scale indicating the relative bearing of the observer. 2. A visual celestial navigation instrument `comprising a support having a light-receiving opening through which srayof light from a eelfstal body is *adapted jtofpass, gjirnbal 'rings secured *to said support, a hanger band suspended frmone of `said rings, an azimuth scale carrid by one of the rings, an altitude and zenith distance arc pivoted to the hanger band centrally of 'the e'ndsof said band and extending to Athe azimuth scale, an index adjustable longitudinally of thearc, a transparent semispherecarried -by the support upon which alight spot Afrom va celestial body is adapted lto be castafter passing through saidlight-receiving opening,A means for locking said gimbal rings, ,said Varc Aand index beingadjustable to register with said light spot on said "semisphere, vand a scale' carried by said arc to measurethe distance'on'sai'd arc between the index andthe azimuth scale to give the altitude ofthe observed bodyv and'to measure the disetancel betweenthe index A.and the pivot` ofthe arcto'givethe zenith distance, the positionjof the arc relative to the azimuth scale indicating th'e'relative bearing of the observer.

3. lA visual celestial navigati-on instrument comprising a support having a light-receiving opening through which a ray of iight from a celestialbody 'is adapted to lpass, gimbal rings secured to said `supporta hanger band suspended from one of said rings. an azimuth scale carried by one of the rings, `an altitude'and zenth'dis'- tance arc pivoted to the hanger band centrally of the ends of said band and extending to the azimuth scale, an index adjustable longitudinally ci the arc, a transparent semisphere carried by the support upon which a light spot from a celestial body is adapted to be cast after passing through said light-receiving openingsaid arcandindex being adjustable to register with said light spot on said semisphere, a scale carried by said arc to measure the distance on said arc between the index and the azimuth scale to give the altitude of the observed body and to measure the distance between the index and the pivot of the arc togive the zenith distance, the position of the arc relative to the azimuth scale indicating the relative bearing of the observer, @gravity-controlled level indicator` carried by the 'semisphere means for locking the indicator instantaneously at the time of observation to register the direction and degree of tilt of the instrument at the time of observation, a second indexmeans carried by the arc""at its pivot movfablel with the-|pivot of the arc into registration with the indicator, and means for locking the "ber carried by the support'and upcnwhi'ch a spot of'ligh't Afrom a celestial body Vis adapted tobe cast, an azimuth ring having an azimuth scaleuniversally mounted upon the support `and Vsurrounding the bowl-like member, a suspension y Vband hung -fr'oxnfthe azimuth ring, an yaltitude Vand v4'zenith distance arc; a pivot securing one end vof the arcvtorthe bandcentrally between the ends of the band, aV reading'glass extending through the pivot, an index on said reading glass, and a leyel carried by the bowl-like member, the

`:reading glassfat lsaid pivot being movableY to bring the index 'on'said glass into registration W-iththe level. an indexslidable 'upon 'sa-idraltitude and zenith -distancearc to Aregister -with a spot of light caston salidbowl-'like Imembenand al scale on the arc t'o 'measure the Iposition 'of :the lastmentioned index relative to the arc.

g5, instrument of -the class described f comprising' asupport, 'a transparent bowl-like member Vcarried l by the support fand upon which a spot'of light'vfjrom -a celestial body -i'sadaptedlto be cast,'-an azimuth ring having an azimuthscale universally mounted upon the support'and surrounding t-he bowl-liker member, a-sus'pension band hung "from 'the azimuth ring, an altitude and zenith Vdistance `arc, a -pivot securing "eine end of -thearc tothe band centrallybetween the ends ofthe band,-a vreading glass "extend-ing through the pivot. an index on 'said eadin'g'glass, a level carried-by the bowl-like member, the reading glass at said pivot being movable to lbring the index on said glass into regstration'with the level, an index slidable upon vsaid altitudeland zenith distance arc to register with "a spot of light cast on'said bowl-like member, a-"scale on the arc to measure the position of the last-mentioned indexrelative to the arc, `and said arc extending in registering relation with said azimuth scale to indicate the relative bearing fromtheobsrvers heading. Y e 6. An instrument of the class described-6mm prising a` support. a transparent bowl-like member carried by the support and upon 'whicha spot of light from av celestial body islfada'ptedto be cast, an azimuth ring having lan'aziinu'th scale universally mounted uponthe support and {surrounding'the bowl-like memberf'a suspension band hung from the azimuth vring,^an*altitude and zenith distance'arc, a pivot securing one end of the arc to the band centrally between the ends of the band. a reading'glass `rextending through the pivot, an index on said 'reading glass, a level carried by the bowl-like membensaid level comprising a casing. a gravity-controlled ball freely movable in said casing, mansfor stopping said ball to 'registerY` itspositio'niri said casing, and a remote"control` means for"'actu ating said last-mentioned means, the 'reading glass at said pivot being vmovable to bring the vindex on said glass into'regis'tration columniation ywith the level, 'an index slidable upon said altitude and zenith `distance arc to register'with a spot of light cast on said bowl-like member.' and a scale on'the arcto measure the position of the last-mentioned index relative toy the arc.

' espasmos H. mossa.

anreisenonsV CIT-ED TheY following references are frecord inthe file of this patent:

UNITED STATES PATENTS 

